Improvement in auger-bits



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Letters Patent No. 87,796, dated Ma/rch. 16, 1869.

IMPROVENIENT IN AUG-ER-BITS.

The Schedule referred to in these Letters Patent and making part of the hams.

To all whom it may concern Be it known that I, HENRY L. SHAILER, of Deep River, in the town of Saybrook, in the county of Middlesex, and State of Connecticut, have invented an Improvement in Double-Twist Augers and Bits and I do hereby declare that the following is a full and exact description thereof, which will enable others skilled in the art to lmake and use my invention', reference being had to the accompanying drawing, and to theletters of reference marked thereon.

The nature of my invention consists in providing double-twist angers and bits, with side, or vertical lips in reserve; which lips are to be placed back of the cutting-edges of the radius, or Hoor-lips, and also back of the cutting line of the spurs, for the purpose of operating as cutters, when the spurs shall be worn ont.

Double-twist augers have heretofore been constructed with horizontal edges, or floor-lips, and vertical edges, or side lips, meeting together atrght angles, like an angular mortise-chisel; and in addition to this arrangement, they have also been constructed with spurs, the edges of which continue the edges of the side, or vertical lips; and also with vertical lips, having their cutting-edges in line with the cutting-edges of spurs in the rear of the floor-lips.

My improvement consists in forming the vertical lips back of the cutting-edges, both of the Hoor-lips, and the spurs, as shown in the accompanying drawing, which is the representation of a double-twist bit,

made in the usual form and way, except that the vertical lips A A are formed in the rear, both of the spurs B B, and the cutting-edgesof the oor-lips O C.`

. It is evident from the representation, that'by'this arrangement of the vertical lips, the durability of the bit l is-doubled, or made equal to a spur-bit and plain bit, as by the setting of the vertical lips back,A the spurs may first be Worn entirely out, and then, by filing the floor-lips to the vertical lips, a perfect plain bit77 produced.

In addition to the main object,my invention has for its further object, to produce smoother work than is usually accomplished by two vertical cutters entering the wood in line with the spurs, designed to perfectly track with them and each other, and also to facilitate the sharpening oftheJ bit, when used as a spur-bit, the vertical lips being less an obstructionfand-.cut ting-edges thereon not essential.

What I claim as my invention, and desire to secure by Letters Patent, isl The vertical lips A A, when formed back from where they have heretofore been placed in their relation to the spurs B B,and cutting-edges O O,.as and for the purposes herein set forth.

HENRY L. SHAILER. Witnesses:

GIDEoN PliRKEEf T. C. SILLIMAN. 

